Low friction slit valve

ABSTRACT

An automatic fluid valve which permits insertion of a surgical instrument therethrough is disclosed and includes an elastomeric slit valve with a plurality of raised surgical instrument engaging protrusions on a proximal surface thereof. Typically, the slit valve is a tricuspid valve, and three protrusions would be provided. The protrusions may take many forms, including barbells or other shaped elements which are insert molded into the slit valve, or bumps which are molded as part of the slit valve. If the protrusions are insert molded, the protrusions are preferably made of a material having a coefficient of friction lower than then the coefficient of friction of the elastomeric, typically silicone, member. If the protrusions are part of the valve, they are preferably coated with a slippery coating such as TEFLON. The faces of the protrusions may also take different forms such as hemispheres, or elongated ribs.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to slit valves. More particularly, this inventionrelates to slit valves which are useful as automatic valves in theproximal portions of trocar assemblies.

2. State of the Art

Endoscopic surgery is widely practiced throughout the world today andits acceptance is growing rapidly. In general, endoscopic surgeryinvolves one or more incisions made by trocars where trocar tubes areleft in place so that endoscopic surgical instruments may be insertedthrough the tubes. Various surgical viewing telescopes, cameras, lenses,or other viewing instrumentation are inserted through one or more trocartubes, while a cutter, dissector, or other surgical instrument isinserted through another trocar tube for the purpose of manipulatingand/or cutting the internal organ or tissue. Sometimes it is desirableto have several trocar tubes in place at once in order to receiveseveral surgical instruments. In this manner, organs or tissue may begrasped with one surgical instrument, and simultaneously may be cut withanother surgical instrument; all under view of the surgeon via theviewing instrumentation in place.

By 1996, it is expected that more than two million additionalendosurgeries will be performed per year that, in 1990, were done viaopen surgery (MedPRO Month, I:12, p.178). The advantages of endoscopicsurgery are clear in that it is less invasive, less traumatic andrecovery is typically quicker. As a result, many new instruments anddevices for use in endosurgery are introduced every year.

Several advances have been made in the art of trocars and trocar tubes.In general, a trocar (stylet) is inserted into a trocar tube (cannula)so that the distal end of the solid trocar extends beyond the distal endof the hollow trocar tube. The trocar and trocar tube are insertedtogether into the patient's body and the trocar is then removed from thetrocar tube leaving the trocar tube in the patient's body to act as apathway for the subsequent insertion of endoscopic tools. Trocar tubesare also used for insufflation and desufflation of certain fluids suchas the insufflation of CO₂ under pressure during various endoscopicprocedures. In these applications, trocars must be fitted with some typeof sealing mechanism to prevent the leakage of gasses. U.S. Pat. No.3,994,287 to Turp et al. discloses a disposable plastic trocar tubehaving a flange portion containing a sealing valve assembly. The valveassembly consists of an elastic ring with an axial opening of reduceddiameter. The elastic ring acts as a sealing gasket between theendoscopic tool and the proximal opening of the trocar.

While the introduction of sealing valve means in trocars has definiteadvantages, disassembly of the valves for cleaning, and the subsequentreassembly and sterilization of these valves is often difficult and timeconsuming. This is particularly so with more sophisticated valves suchas the ball valve disclosed in U.S. Pat. No. 4,379,458 to Bauer et al.As a result of the difficulties in cleaning the valves of the reusabletrocars, a large disposable trocar market has emerged. The use ofdisposable trocars, however, is costly both in actual per operationequipment costs, as well as in the disposal of the medical waste.

Other improvements in trocar assemblies include various safety systemswhich sometimes interact with sealing valve mechanisms to preventaccidental punctures by the sharp distal end of the trocar. U.S. Pat.No. 4,654,030 to Moll et al. discloses a trocar having a coaxial springloaded safety shield which extends over the distal sharp point of thetrocar. A trocar tube having an elastomeric gasket and a flapper valveinteracts with the safety shield so that the sharp point of the trocarcan only be exposed when the flapper valve is opened. Similararrangements are disclosed in U.S. Pat. No. 4,931,042 to Holmes et al.and U.S. Pat. No. 5,032,206 to Lander.

Other innovations in trocar tubes include the addition of helicalthreads on the surface of the trocar tube, as shown in U.S. Pat. No.5,009,643 to Reich et al., in order to better hold the trocar tube inplace in the patient.

Perhaps the most commonly used trocar assembly today is the safetytrocar with flapper valve assembly similar to those described by Moll etal., Holmes et al., and Lander. Some of the improvements to these typesof trocars include an improved valve seat and plug for the flapper valveto assure a gas-tight seal when the flapper valve is closed as isdescribed in U.S. Pat. No 5,053,016 to Lander. It is, however, acontinuing disadvantage of trocar tubes having sealing valves that theyare either difficult to disassemble, sterilize, and reassemble, oralternatively that they are intended for disposal after a single use.These disposable trocar tubes are relatively expensive and, as mentionedabove, endoscopic surgical procedures often require several trocar tubesto be in use simultaneously.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a reusablesurgical trocar and tube with a removable disposable sealing valveportion.

It is also an object of the invention to provide a surgical trocar tubewith a sealing valve portion that is easily removed and replaced.

It is another object of the invention to provide a surgical trocar tubehaving a removable sealing valve portion which remains securely attachedto the trocar tube when in use.

It is a further object of the invention to provide a number of differenttypes of sealing valve portions which are usable with a reusable trocartube to suit particular requirements of different procedures.

It is yet another object of the invention to provide a number ofdifferent reusable trocars for use with the disposable valve assemblyand reusable trocar tube of the invention, including a safety tiptrocar, to suit different requirements of different procedures.

It is still another object of the invention to provide a safety tiptrocar which is easily cleaned for reuse.

It is even a further object of the invention to provide a trocarassembly having all of the advantages of the existing disposable trocarassemblies of the art while having the additional advantage of beingsterilizable and reusable except of a removable sealing valve assembly.

An additional object of the invention is to provide a low friction slitvalve which may be used in a trocar assembly.

Another object of the invention is to provide an automatic insufflationvalve which is opened by the coupling of a connection such as a luermechanism to the insufflation valve, and closed by the uncoupling of thesame.

In accord with these objects which will be discussed in detail below,the trocar assembly of the present invention includes three majorassemblies: a reusable trocar having a handle; a reusable cannula(trocar tube) having a base; and a removable disposable sealing valveassembly. The sealing valve assembly is removably coupled to the cannulabase and the trocar is insertable through the sealing valve assemblyinto the cannula. Typically, the trocar handle covers at least a portionof the sealing valve assembly when the reusable trocar is fully insertedinto the cannula. The trocar is removable from the cannula and sealingvalve assembly without uncoupling the sealing valve assembly from thecannula.

The sealing valve assembly preferably includes a body having a receivingwell for holding a sealing valve such as a slit or flapper valve and auniversal washer combination. A valved side port is optionally providedon the body. An annular snap-on valve cap covers the universal washerand slit or flapper valve when assembled and holds them in place.

The coupling of the valve assembly to the cannula base is accomplishedby threaded means, bayonet means, spring biased quick connect means suchas a latch, or other such means on the valve assembly and/or on thecannula base. The cannula is preferably a metallic shaft which is insertmolded into the cannula base. A metallic cannula sleeve having externalthreads for anchoring to fascia and an optional cannula seal ring areprovided on a portion of the cannula close to the cannula base. Thepreferred cannula base includes a wide receiving mouth for holding thevalve assembly and a somewhat narrower throat leading to the cannula.The wide receiving mouth is preferably provided with side openings toaccommodate the side port of the valve assembly and for removablycoupling the valve assembly to the cannula base. The valve assemblypreferably has a relatively wide body which fits snugly inside the widemouth of the cannula base and a relatively narrow distal end with afluid sealing means such as an O-ring or other sealing mechanism forsealing with the throat of the cannula base.

A number of different trocars are provided for use with the trocarassembly of the invention, including a blunt tip, a sharp pyramid tip,and a spring-loaded safety tip. According to one embodiment, the tipsmay be interchangably screwed into the distal end of a trocar rod.According to a preferred safety tip trocar embodiment, a spring biasedblunt tipped rod is provided which extends within and beyond a sharptip. A spring which biases the rod is housed in the trocar handle andthe spring and rod are easily removable from the trocar through a screwcap in the top of the handle. In this manner, after use, the componentsmay be disassembled, cleaned, reassembled, and autoclaved prior toreuse.

Other aspects of the invention include: providing the side port of thevalve assembly as an automatic side port valve which opens only when amale luer fitting is inserted into side port; providing improvedproximal automatic valve means such as a tricuspid slit valve withcontact bumps or rails in order to reduce friction between thedisposable valve assembly and trocars or other instruments insertedthrough the valve assembly; and providing anti-rotational mating splinesor grooves on two or all three of the valve assembly, the trocarassembly, and the cannula assembly so as to prevent rotation of theassemblies relative to each other.

Additional objects and advantages of the invention will become apparentto those skilled in the art upon reference to the detailed descriptiontaken in conjunction with the provided figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view in partial cross section of a first embodiment ofthe invention;

FIG. 1a is a cross section along the line A--A in FIG. 1;

FIG. 2 is an exploded view of the embodiment of FIG. 1;

FIG. 2a is a sectional view along line A--A in FIG. 2;

FIG. 2b is an enlarged detail of a portion of FIG. 2a identified by thecircle B;

FIG. 2c is a sectional view along line C--C of FIG. 2;

FIG. 2d is an enlarged detail of a portion of FIG. 2c identified by thecircle D;

FIG. 2e is an enlarged plan view of the universal washer;

FIG. 2f is an enlarged plan view of the tricuspid valve;

FIG. 2g is a view similar to FIG. 2f but of an alternate embodiment ofthe tricuspid valve;

FIG. 2h is a view similar to FIG. 2f but of a further alternateembodiment of the tricuspid valve;

FIG. 2i is a side elevation view of the tricuspid valve of FIG. 2g;

FIG. 2j is a side elevation view of the tricuspid valve of FIG. 2h;

FIG. 2k is a view similar to FIGS. 2i and 2j but of a further alternateembodiment of the tricuspid valve;

FIG. 2l is a side elevation view of bump insert used in the valve ofFIGS. 2g and 2i;

FIG. 2m is a side elevation view of a bump insert used in the valve ofFIGS. 2h and 2j;

FIG. 2n is a top plan view of an alternate embodiment of a bump insert;

FIG. 2o is a view similar to FIG. 2n but of a further alternateembodiment of a bump insert;

FIG. 2p is a cross sectional view of a flapper valve arrangementaccording to another embodiment of the invention;

FIG. 2q is a cross sectional view of another embodiment of a flappervalve in a closed position in a valve body having a universal washer;

FIG. 2r is a view similar to FIG. 2q showing the flapper valve held inan open position by a J-hook cautery probe;

FIG. 2s is a top view of the assembly shown in FIG. 2q;

FIG. 3 is a view similar to FIG. 1 showing an embodiment of a valveassembly which includes a side port;

FIG. 4 is a partial exploded view, similar to a portion of FIG. 2,showing a second embodiment of the coupling mechanism for the valveassembly and cannula base;

FIG. 5 is a view similar to FIG. 4 showing a third embodiment of thecoupling mechanism for the valve assembly and cannula base;

FIG. 6 is a view similar to FIGS. 4 and 5 showing a fourth embodiment ofthe coupling mechanism for the valve assembly and cannula base;

FIG. 7 is a longitudinal cross sectional view of another embodiment ofthe valve assembly for use with a cannula base coupling as shown in FIG.5;

FIG. 8 is a view similar to FIGS. 1 and 3 showing a different embodimentof trocar handle;

FIG. 9 is a side elevation view of the trocar handle shown in FIGS. 1-3;

FIGS. 9a-9c are side elevation views of different trocar tips;

FIG. 9d is a top end view of the trocar handle taken in the directionD--D of FIG. 9;

FIG. 9e is a bottom end view of the trocar handle taken in the directionE--E of FIG. 9;

FIG. 10 is a side elevation view in partial longitudinal section of thesafety trocar tip of FIG. 9b;

FIG. 10a is a longitudinal cross sectional view of recessed hollow forreceiving the spring shown in FIG. 10;

FIG. 10b is a longitudinal cross sectional view of the piercing pointshown in FIG. 10;

FIG. 10c is a side elevation view of the blunt spring biased safety tipshown in FIG. 10;

FIG. 11 is an exploded perspective view of yet another embodiment of thevalve assembly and cannula base;

FIG. 11a is a perspective view of the trocar handle for use with thevalve assembly and cannula base of FIG. 11;

FIG. 11b is a perspective view of the valve body of FIG. 11;

FIG. 11c is a longitudinal cross sectional view of the safety trocar foruse with the arrangement of FIG. 11;

FIG. 11d is a top view of the trocar of FIG. 11c;

FIG. 11e is a cross-sectional view the apparatus of FIGS. 11 and 11aassembled as a non-safety sharp tipped trocar;

FIG. 11f is a cross section through line F--F of FIG. 11e;

FIG. 11g is a view similar to FIG. 11, but of a slightly differentembodiment of the invention;

FIG. 11h is a view similar to FIG. 11e but of the embodiment of FIG.11g;

FIG. 12 a and 12b are side views in partial cross section of a preferredvalve means for use with the invention shown respectively in closed andopen positions; and

FIG. 12a c is a end view of the plunger of the preferred valve means ofFIGS. 12a and 12b.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to FIGS. 1, 1a and 2, the trocar assembly 10 of thepresent invention generally includes a hollow trocar tube or cannulaassembly 11 having a cannula 12 insert molded in a cannula base 14, asealing valve assembly 16 removably coupled to the cannula base 14, anda trocar assembly 18 having a trocar 19 with a distal tip 20 and aproximal handle 21 which is removably inserted through the valveassembly 16 and the cannula 12.

The cannula 12 of the cannula assembly 11 is preferably provided with athreaded cannula sleeve 13 and an optional external groove 131 forreceiving an optional seal ring 15 which is mounted on a proximal end ofthe cannula adjacent the cannula base 14 as seen in FIG. 1. The sealring 15 is advantageous in forming a seal on the surface (skin) of apatient and preventing leakage of gases and body fluids from theincision site. If desired, the cannula 12 and threaded cannula sleeve 13can be formed as a single integral part.

According to a first embodiment of the invention, the cannula base 14 ispreferably provided with one or more external flanges 140 for gripping.Internal the cannula base 14, a passageway 141 is provided. Passageway141 includes distal opening 142 in which the cannula 12 is held, acylindrical passage 143, a threaded portion 144, and a tapered portion145. As will be discussed in more detail hereinafter, the cylindrical143, threaded 144, and tapered 145 portions of passage 141 are used toreceive and coupled to the valve assembly 16. It will be appreciatedthat the cannula 12 and cannula base 14 are preferably formed in amanner such that they are easily cleaned (by autoclaving or othersterilization techniques) and are intended to be reusable.

The valve assembly 16 of the embodiment of FIGS. 1 and 2 includes avalve body 160, a sealing mechanism such as an O-ring 161, a slit (e.g.,tricuspid) valve 162, a universal washer 163, and a cap 164. Theexternal surface of the valve body 160 includes a distal cylindricalextension 165. The cylindrical extension 165 may either be formed with amolded sealing protrusion which acts as a sealing mechanism, or with adistal groove 165a which receives the sealing O-ring 161. The externalsurface of the valve body 160 also includes a first threaded section 166which mates with threads 144 of the cannula passageway, a taperedsurface 167 which increases in diameter as it extends from the distalend to the proximal end and which mates with tapered surface 145 of thecannula passageway, bowed finger indentations 168, a proximal secondthreaded section 169, and ratchet teeth 170 between the threaded section169 and the finger indentations 168.

Comparing FIGS. 1 and 2, it will be appreciated that the valve body 16is provided with an internal throughbore 171 which communicates with thecannula 12 when the valve body 160 is coupled to the cannula base 14.Throughbore 171 widens at 172 at its proximal end, and extends into awell 173 which receives the slit valve 162 and the universal washer 163.These are held in place by a covering cap 164 which engages threads 169surrounding the proximal end of the valve body 16. As shown in FIGS. 2and 2a, the covering cap 164 includes a central through bore 174,internal threads 175, an internal ratchet locking surface 176, anexternal splines 177. It will be appreciated that after the slit valve162 and the universal washer 163 are placed in the well 173 of the valvebody 16, the covering cap 164 is placed over the threads 169 of thevalve body 16 and turned until internal thread 175 of the cap engage thethreads 169 of the body and the pieces are brought snugly together. Thecentral throughbore 174 in the covering cap 164 provides a passage forthe trocar 19 through the universal washer 163 and the slit valve 162,into the internal through bore 171 of the valve body 16 and thus intothe cannula 12 as shown in FIG. 1.

It is contemplated by the present invention that once assembled, thevalve body 160, slit valve 162, universal washer 163 and covering cap164 will not be disassembled and that the entire valve assembly will beremoved from the cannula base 14 after use for disposal. With this inmind, the valve body 160 another the covering cap 164 are provided witha ratchet-like locking means 170, 176 respectively. FIGS. 2a-2d showthese in greater detail. Referring now to FIGS. 2a-2d, it will be seenthat the internal lip of the covering cap 164 is provided with aplurality of ramped ratchet teeth 176 and the distal part of theproximal threaded portion 169 of the valve body 160 is provided with aplurality of oppositely ramped ratchet teeth 170. Those skilled in theart will appreciate that when the covering cap 164 is screwed tightlyonto the valve body 160, these respective ramped teeth (176 and 170)engage each other to allow a screw coupling or the pieces whilepreventing an uncoupling rotation of the pieces.

Those skilled in the art will appreciate that the completed valveassembly 16 may be coupled to the cannula base 14 by holding the valvebody 160 at its bowed finger indentations 168, inserting the cylindricalextension 165 of the valve body 160 into the cylindrical passage 143 ofthe cannula base 14, and turning the valve body 160 so that the distalthreads 166 engage the threads 144 of the cannula base and the twopieces are brought snugly together as shown in FIG. 1. When thathappens, O-ring 161 seats inside the cylindrical passage 143 of thecannula base 14 and provides a fluid-tight coupling of the throughbore171 with the cannula 12. Likewise, the completed valve assembly 16 maybe removed from the cannula base 14 by gripping the valve body at fingerindentations 168 and rotating in the opposite direction until the valvebody is uncoupled from the cannula base 14.

As mentioned briefly above, the covering cap 164 of the valve assembly16 is provided with external surface splines 175. These are provided forengagement with internal splines 202 of the distally extending sleeveportion 201 of the trocar handle 21. As seen best in FIG. 1, when thereusable trocar 18 is inserted through the throughbore 174 in the valvecovering cap 164, and through the washer 163, slit Valve 162,throughbore 171 in the valve body 160, and the cannula 12, the internalsplines 202 in the trocar handle 21 engage the external splines 175 onthe covering cap 164 of the valve body 160 as the trocar tip 20 extendspast the distal end of the cannula 12. These splines prevent the trocarhandle from rotation relative to the valve body 14 (compare FIG. 8described below). During insertion, flaps of the slit valve 162 arepushed into the widening 172 of throughbore 171. Also, during insertion,the washer 163 (and to a lesser extent, the slit valve 162) seals aroundthe trocar 19 and prevent fluids or gases which might work their way upthe trocar assembly in an annulus between the trocar 19 and the innerwall of the cannula and valve assembly from escaping. Upon withdrawingthe trocar 19 from the cannula 12 and valve assembly 16, the slit valve162 closes automatically and prevents the escape of gas or fluids.

The trocar handle 21 and cannula base 14 are both preferably molded froma steam autoclavable plastic or polymer such as "UDEL Polysulfone" orits equivalent, although all or parts of one or the other can be made ofmetal. The valve body 160 and covering cap 164 are each preferablyformed from an injection molding of plastic such as polypropylene,polycarbonate or their equivalents. The trocar 19 is preferably formedfrom stainless steel and is preferably insert molded into the handle 21.Likewise, the cannula 12 with integral sleeve 13 is preferably formedfrom stainless steel which is insert molded into the cannula base 14.The cannula sealing ring 15, the slit valve 162, and the universalwasher 163 are each preferably molded from medical grade silicone. Thecannula sealing ring 15, therefore, has enough elasticity to bestretched over the cannula sleeve 13 so that its central hole 151embraces groove 131 in the cannula sleeve 13. The slit valve 162 anduniversal washer 163 have sufficient elasticity to allow passage oftrocar 19 while effectively sealing the valve body from entry or exit offluids.

FIG. 2e shows an enlarged plan view of the universal washer 163. Theuniversal washer 163 is provided with a pair of annular rings 163a, 163bon opposite sides of central opening 163c. These annular rings addflexibility to the washer so that little resistance is offered wheninserting and removing the trocar.

FIG. 2f shows an enlarged plan view of the tricuspid valve 162. Thetricuspid valve is typically constructed of a silicone disk with threeslits 162a, 162b, 162c converging at the center of the disk. When atrocar is inserted into the valve, portions of the valve between theslits are pushed apart. The silicone material offers resistance,however, and this impedes insertion and removal of the trocar. Whilelubricity could be added to the silicone valve by forming the siliconewith a lubricant, or by adding lubricant to the outer surface of thevalve, in accord with a preferred aspect of the invention, lubricity isadded to the tricuspid valve by providing bumps or buttons made out ofpolyethylene, polypropylene, TEFLON (a trademark of E. I. DuPont deNemours of Delaware), or equivalents thereof which preferably extendthrough the valve. FIGS. 2g and 2h show alternate configurations of atricuspid valve 262 and 362. The bumps 262a-262c or 362a-362c are placedon the surface of the silicone disk in the areas between the slits. Thebumps may be glued or snap fit through holes in the disk. They may bealmost any shape but an elongated shape which extends radially away fromthe center of the disk such as shown in FIG. 2h is preferred. When thetrocar or other surgical instrument is inserted through the valve, andthe portions of the valve between the slits is spread, the bumps restagainst the surface of the trocar or other instrument and provide aslippery surface contact so that the trocar or other instrument iseasily inserted and removed.

As shown in FIGS. 2i and 2i, the bumps may formed from barbell-likeinserts having an upper bump 262a, a middle stem 262d and a lower bump262e. As mentioned above, the upper and lower bumps may be hemisphericalor hemi-elliptoid. The barbell-like pieces are insert molded into thesilicone disk. Since in practice, it is only necessary to provide bumpson the proximal side of the disk, the bumps shown on the distal side ofthe disk in FIG. 2i are for anchoring purposes and do not affect thefrictional relationship of the valve and the trocar or other surgicalinstrument extending through the valve. In this regard, it will beappreciated that the bump-forming inserts may take many forms such as,for example, as shown in FIGS. 2j, 2m, 2n, and 2o. In FIGS. 2j and 2m,the inserts are formed with an upper bump 362c, a middle stem 362d, anda lower flange 362e which aids in anchoring the bumps when they areinsert molded in the silicone disk. In order to expedite the insertmolding process, a plurality bumps may be formed as a single moldedpiece as shown in FIGS. 2n and 2o. In FIG. 2n, bumps 562a-562c arecoupled by respective stems (not shown) to a web 562 which may take theform of a mesh or a ring. The web 562 is insert molded in the siliconedisk. When the slits are made in the disk to create the tricuspid valve,the mesh or ring may or may not be cut by the slits since after the diskis molded around the web, the integrity of the ring or mesh is no longerimportant. It only acts as an anchor for the bumps, and so long as apiece of the ring is attached to the bump, the bump will be securelyanchored in the disk. A similar arrangement of ring 662 is shown in FIG.2o where bumps 662a-662c are attached to radial arms 662d-662f by stems(not shown). The radial arms displace the bumps from the ring so thatthe ring may be located outside the range of the slits.

Another embodiment of the tricuspid valve 462 is shown in FIG. 2k. Inthis embodiment, bumps 462a-462c are formed directly on the disk 462(i.e., integral therewith) by molding the disk in a mold having recessesfor the bumps. The bumps are then coated with TEFLON (shown as a shadedportion in FIG. 2k) or another suitable slippery surface material.Alternatively, the entire surface of the disk is coated with TEFLON oran equivalent thereof. When the trocar enters the tricuspid valve, thebumps engage the surface of the trocar reducing the area of frictionalengagement between the valve and the trocar. The TEFLON coating on thebumps further reduces friction between the trocar and the valve wheninserting and withdrawing the trocar.

FIG. 2p shows another type of valve arrangement 200 which offers littleresistance to the insertion and removal of trocars and surgicalinstruments. Valve arrangement 200 includes a proximal washer 263 havinga central opening 263c and oppositely extending annular bumps 263a,263b. A distal flapper valve 265 includes a resilient arm 266 coupled toa ring 267 which may be integral therewith. Ring 267 has a centralopening 268 and a proximal annular shoulder 269. An insert 270 ofpolypropylene or its equivalent has a frustoconical proximal end 271, anarrow diameter middle 272 and a flanged distal end 273. Insert 270 isheld in the central opening 268 of ring 267 with its frustoconical end271 resting in shoulder 269, and the flanged end 273 resting against thedistal side of opening 268. The resilient arm 266 biases the ring 267and the insert 270 against the washer 263 as shown in solid lines inFIG. 2p. In this position, the frustroconical end 271 of the insert 270engages the annular bump 263b of washer 263 and seals the centralopening 263c. When a trocar is inserted through the central opening263c, the flapper valve 265 is moved by the trocar to the position shownin dotted lines (phantom) in FIG. 2p. The slippery insert 270 offerslittle or no resistance to the trocar or other surgical instrumentduring insertion and removal. When the trocar or other surgicalinstrument is removed, the resilient arm 266 biases the valve shut. Itwill be appreciated by those skilled in the art that universal washer263 and the flapper valve 265 shown in FIG. 2p are appropriately housedin the valve assembly of the invention.

FIGS. 2q through 2s show a presently preferred embodiment of a valvearrangement 300 in a valve body 361 having a side port 379, athroughbore 319, a proximal valve body cap 375 and a distal O-ring 161.The proximal end of the valve body 361 is provided with a washerreceiving annular groove 361a. A universal washer 363 having a centralopening 363c, an intermediate annular ripple 363b, and an outer circularflange 363a is placed at the proximal end of the valve body 361 so thatthe flange 363a engages the groove 361a and the central opening 363csubstantially aligns with the throughbore 319 as shown in FIG. 2q. Avalve body cap 375 is provided with a central opening 375c, an innerannular flange 375a and an outer annular flange 375b. The annularflanges in the valve body cap engage the universal washer as shown inFIG. 2q. In particular, the outer flange 375b presses the universalwasher against the groove 361a in the valve body 361 and the innerflange 375a surrounds the central opening 363c of the washer 363.

The valve body 361 is further provided with a hinge pin 376 adjacent theside port 379. Hinge pin 376 supports a swing arm 368 and a torsionspring 366. Swing arm 368 is provided with a central spherical button369 which takes the form of ball joint for carrying a sealing cap 370.The sealing cap 370 has a lower central cylindrical socket 374 forreceiving the ball 369 (with the ball and socket providing a centeringand seal adjusting function), an upper circular lip 372 for engagingwasher 363, and a laterally extending downward curved tongue 373. Asseen in FIG. 2q, the sealing cap 370 is held by swing arm 368 and isbiased against the washer 363 by the torsion spring 366. It will beappreciated that the upper circular lip 372 underlies the inner flange375a of the valve body cap 375 with the universal washer 363therebetween. Thus, when the swing arm 368 is biased by the torsionspring 366 to the position shown in FIG. 2q, the upper circular lip 372of the sealing ring presses against the universal washer 363 (which inturn is limited in its movement by the flange 375a of the valve body cap375), thereby making a fluid tight seal.

When a surgical probe, such as J-hook cautery probe 419 is inserted intothe valve body 361 through the central opening 375c in the valve bodycap 375, the distal end 420 of the probe pushes against the sealing cap370 and moves the swing arm 368 against the bias of spring 366.Concurrently, the edge of the central opening 363c of the universalwasher 363 is bent inwards, thereby keeping a fluid seal between theprobe 419 and the throughbore 319 of the valve body. The lateraldownward extending tongue 373 of the sealing cap 370 assumes theposition shown in FIG. 2r and rests against the side of the probe 419allowing it to be moved in and out of the valve body without entanglingthe sealing cap. It will be appreciated from FIG. 2r that the length andcurvature of the tongue 373 is sufficient to prevent the J-hook end 420of probe 419 from catching the edge of the sealing cap and pulling itoff the swing arm.

Turning now to FIG. 3, in accord with another embodiment or a valveassembly 316, the valve body 360 is provided with a side port 380 forcoupling to a fluid conduit (not shown). In this embodiment of the valvebody 360, the side port 380 is seen to include a manual stopcock(compare FIG. 7 described below) and access through side port 380 ismanually controlled by the practitioner. Those skilled in the art willappreciate that when the trocar 19 is removed from the valve body 360,fluid flow is permitted between the side port 380 and the cannula 12 ifthe manual stopcock is in an open position.

As mentioned above, the valve body and the cannula base are providedwith coupling means so that the valve body may be attached to thecannula base before use and removed from the cannula base for disposalafter use. FIGS. 1 and 2 described a screw coupling between the valvebody and the cannula base. FIGS. 4-6 show other types of coupling meansfor coupling the valve body to the cannula base.

FIG. 4 shows a valve assembly 416 and a cannula base 414 which areprovided with a bayonet coupling. In this embodiment, the valve body 460of assembly 416 is provided with a cylindrical extension 465 having apair of radially outward extending knobs 466a, 466b. Cylindricalextension 465 is also provided with an O-ring 161 which is substantiallythe same as the O-ring described above. Cannula base 414, according tothis embodiment, is provided with a pair of bayonet grooves 464a, (464bnot shown in the drawing) with knob receiving ends 481a, (481b not shownin the drawing) on the inner surface of its cylindrical passage 443.Those skilled in the art will appreciate that when the cylindricalextension 465 of valve body 460 is aligned so that the knobs 466 enterthe grooves 464 of the cannula base 414, the two pieces may be pressedtogether. After the pieces are pressed snugly together, the pieces arerotated until the knobs 466 enter the knob receiving ends 481 of thebayonet grooves 464. The pieces are separated by twisting and pullingapart as understood in the art of bayonet coupling.

FIG. 5 shows a valve assembly 516 and a cannula base 514 which couple bymeans of a circumferential groove and a blade latch. In this embodimentthe cylindrical extension 565 of the valve body 560 is provided with acircumferential groove 566. Cannula base 514 is provided with a slidingblade latch 564 which transects cylindrical passage 543. The blade latchhas a circular opening 583 and a push button release handle 584 which isbiased outward by a spring 585. When the blade latch is biased outwardfrom the cannula base as shown, the circular opening 583 is axiallyoffset from the cylindrical passage. In order to insert the valve body560 into the cannula base 514, the push button 584 is depressed againstspring 585 until the circular opening 583 is coaxial with cylindricalpassage 543. After the cylindrical extension 565 of the valve body 560is inserted into the cylindrical passage 543 of the cannula base 514,the push button 584 is released and spring 585 biases the blade latch toan offset position wherein the edge of opening 583 engages the groove566. Releasing the two pieces is accomplished by pressing the pushbutton and pulling them apart.

FIG. 6 shows a valve assembly 616 and a cannula base 614 which have ascrew coupling different from that shown in FIGS. 1 and 2. Here, valvebody 660 is provided with a distal sleeve 686 surrounding itscylindrical extension 665. Distal sleeve 686 has internal threads 666which engage external threads 644 provided on the cannula base 614.Coupling and uncoupling of these embodiments is similar to thatdescribed in FIGS. 1 and 2.

As mentioned above, the valve body may be provided with a side port. Oneexample of a side port (manual stopcock) was described in FIG. 3. FIG. 7shows another example of a side port 780 in a valve assembly 716. Here,side port 780 provides a female luer lock 790 and a preferably polymericsliding valve 791 biased to a closed position against seat 792 by spring793. Inserting a male luer, presses the valve 791 away from seat 792 toopen a fluid passage. Removing the male luer allows valve 791 to be onceagain biased against seat 792 by spring 793. Additional detail regardingthe valve is provided hereinafter with reference to FIGS. 12a-12c.

As mentioned above with reference to FIGS. 1 and 2, the trocar handle 21is preferably provided with anti-rotational means; namely a sleeve 201with internal splines 202 which engage external splines 175 on thecovering cap 164 of the valve body 160. In some embodiments, however,this anti-rotational scheme is not sufficient insofar as the valve body160 is not prevented from rotation relative to the cannula base 14. FIG.8 shows a different embodiment of the anti-rotational means where thetrocar handle 821 is provided with an extended sleeve 801 havinginternal splines 802. In this embodiment, a cannula base 814 is providedwith proximal external splines 875. As can be seen in FIG. 8, theextended sleeve 801 of the trocar handle 821 extends long enough toengage the splines 875 on the cannula base 814. This arrangementprovides complete anti-rotational protection among the trocar handle,the valve body, and the cannula base. From the foregoing descriptions,it will be appreciated that when the trocar handle 821 and cannula base814 are used in conjunction with a valve body having a side port such asthose shown in FIGS. 3 and 7, a longitudinal cutout will be needed inthe sleeve 801 to allow passage of the sleeve over the side port in thevalve body.

Several different types of trocars can be used with the trocar assemblyof the invention. FIGS. 9 through 10c show details of different trocarsand trocar handles.

Turning now to FIGS. 9-9e, a number of different tips 20, 920, 1020 maybe provided on trocar 19 which is preferably insert molded into trocarhandle 21. Trocar tip 20 is blunt and is preferred when a small incisionsuch as might have been made by a scalpel blade or by a Veress needle isalready available. Trocar tip 920 is a sharp pointed tip and ispreferred when the trocar is used to incise the patient while insertingthe trocar tube or cannula. When incising, however, it is important thatthe trocar not be inserted too deep, lest it pierce an internal organ.To guard against such an unintentional piercing, a safety tip 1020 maybe provided on the end of a trocar for use with the trocar assembly ofthe invention. It should be appreciated by those skilled in the art willthat any of the disclosed trocars may be provided with integral tips orwith screw-in tips. In the screw-in tip arrangement, the distal end ofthe shaft of the trocar 19 would terminate with a male thread or afemale threaded recess. Conversely, the proximal end of the tip portionwould be provided with a female threaded recess or a male thread whichwould mate with the distal end of the shaft. With this arrangement, onlythe distal tip portion would need to be discarded after the tip was nolonger usable.

Turning now to FIGS. 10, 10a, 10b, and 10c, a first embodiment of asafety trocar 1020 is provided. Safety trocar 1020 has a distal sleeve1002 extending from shaft 1018 (which may extend to the handle or beprovided with a screw mechanism for mating with another shaft) withinwhich a spring 1008, a blunt tip 1006, and a piercing cylinder 1004 aremounted. The distal sleeve 1002 has a proximal end wall 1003 againstwhich a proximal end of coil spring 1008 rests. The blunt tip 1006 has arounded or otherwise blunt shaped distal end 1011 and a proximal springengaging knob 1017. The blunt tip 1006 is also provided with a forwardstop collar 1013 adjacent the spring engaging knob 1017. The piercingcylinder 1004 has a bias cut sharp distal end 1009, an interior forwardstop shoulder 1005, and a reduced outer diameter sleeve mating portion1007. Those skilled in the art will appreciate that the safety tip isassembled by placing the spring 1008 in the sleeve 1002, placing theblunt tip 1006 on top of the spring 1008, placing the piercing cylinder1004 over the blunt tip and spring, and pressing the reduced diameterproximal end 1007 of the piercing cylinder into the sleeve 1002 againstthe force of spring 1008. The sleeve 1002 and piercing cylinder 1004 arepreferably coupled by press fitting and mechanical staking. The distalend of the assembled safety trocar is shown in FIG. 10. Those skilled inthe art will appreciate that when the trocar incises the patient, theblunt tip is pressed back against the spring until the sharp piercingcylinder is exposed to perform the incision. After the trocar piercesthe outer cutaneous wall, the blunt tip is biased back to its originalposition as shown in FIG. 10 and offers a palpable resistance should thetip of the trocar contact an internal organ.

FIGS. 11, and 111-11f show features of yet another embodiment of theinvention. In FIGS. 11, 11b, 11e, and 11f, it can be seen that the valveassembly 1160 has a body 1160 which carries a distal O-ring 161. Oneside of the body 1160 is provided with a resilient tongue 1194 carryinga ramped tooth 1166 and a release button 1168 for releasably mating withthe cannula base 1114. A side port 1180 is provided on the other side ofthe body 1160 as shown in FIG. 11b. Body 1160 has a cylindricalthrougbore 1171 which widens into a well 1173. The well 1173 receivesthe slit valve 162 and washer 163. A lip 1198 surrounding well 1173 isprovided with two or more radially extending ramped mating teeth 1169for mating with the valve Cap 1164.

The valve cap 1164 has a central opening 1174 for receiving a trocar orother endoscopic instrument and two or more radial holes 1177 forengaging ramped teeth 1169. Holes 1172 are separated by ribs 1199. Thevalve assembly is assembled by placing slit valve 162 and universalwasher 163 into the well 1173 or cap 1164 and snapping the valve cap1164 over the lip 1198 of the valve body 1160 so that ramped teeth 1169engage holes 1177. It will be appreciated that the teeth 1169 are rampedso that the cap 1164 may not be easily removed once the valve assemblyis assembled.

The cannula base 1114 of the embodiment of FIGS. 11a-11f has a proximalmouth 1145 and a distal throat 1143. Mouth 1145 is provided with alongitudinal side cutout 1180a for receiving side port 1180 of the valvebody 1160 and a Similar though shorter side cutout 1195 for receivingrelease button 1168 of the valve body 1160. Distal of cutout 1195, ahole 1144 is provided for receiving and engaging ramped tooth 1166 ofthe valve assembly. The valve assembly is removably coupled to thecannula base by inserting the narrower distal portion 1165 of the valveassembly into the mouth 1145 of the cannula base 1114 so that the sideport 1180 aligns with the cutout 1180a. Pressing the pieces togetherengages the O-ring 161 on the valve assembly 1116 with the throat 1143of the cannula base 1114, and the tooth 1166 of the valve assembly withthe hole 1144 in the cannula base 1114. It will be appreciated that thetooth 1166 is ramped to facilitate installation of the valve assembly inthe cannula base and to prevent accidental removal. The release button1168, when pressed, moves the tongue 1194 radially inward and thusremoves the tooth 1166 from engagement with the hole 1144. It willtherefore be appreciated that the pressing of the release button 1168allows the valve assembly 1116 to be removed from the cannula base 1114by pulling it out of the cannula base.

The trocar handle 1121 of FIGS. 11a-11f is provided with a sleeve 1101having one or more internal splines 1102. When the trocar 1119 isinserted through opening 1174 in the cap of the valve assembly, splines1101 fit snugly in the indentations 1175 between ribs 1199 and preventrotation of the trocar handle relative to the valve assembly and cannulabase. It will be appreciated that the splines 1102 of the handle 1121and the teeth 1169 of the valve assembly are properly dimensioned so asnot to interfere with each other when they are both in contact with thevalve cap 1164.

A preferred safety tip trocar is shown in detail in FIGS. 11c and 11d. Ahollow trocar cylinder 1118 having a sharp distal end 1109 is insertmolded in handle 1121. A sliding blunt tip safety rod 1119 extendsthrough the hollow trocar cylinder 1118 and beyond its distal end 1109.The proximal end of the rod 1119 is provided with a flange 1113a whichlimits its forward movement in the cylinder 1118, as well as acylindrical hollow 1113b for receiving a spring 1108. Handle 1121 isprovided with a cylindrical opening 1123 substantially coaxial withcylinder 1118 and rod 119. A cylindrical cap 1103 is removably mountedby a threaded connection in cylindrical opening 1123 and the spring 1108is interposed between the cap 1103 and the distal end of the hollow1113b in the rod 1119. The spring 1108 biases the blunt tipped rod toits forward safety position as described above. The removable cap 1103allows the removal of the spring 1108 and the rod 1119 for cleaning.

FIG. 11e is a longitudinal cross sectional view of the invention shownin FIG. 11 with a different type of trocar 1219 and trocar handle 1221.FIG. 11f is a cross section through the line F--F in FIG. 11e. Here thetrocar is substantially the same as that described above with referenceto FIG. 9c and the trocar handle 1221 is a solid piece into which trocar1219 is insert molded. Trocar handle 1221 is in most ways the same astrocar handle 1121 described above, but for the spring holding cap 1103.FIGS. 11e and 11f show the relationship between cannula base 1114, valveassembly 1116, and trocar handle 1221. As shown, the cannula 1212 isprovided with an integral proximal threaded collar 1213 as describedabove with reference to FIGS. 1 and 2.

Viewing FIGS. 11e and 11f, it can also be seen that the valve body 1160comprises three substantially concentric cylinders 1160a, 1160b, 1160c.The innermost cylinder 1160a provides the through passage for the trocarand is coupled at its proximal end to a middle cylinder 1160b. Thecoupling of the innermost cylinder 1160 with the middle cylinder 1160bforms the proximal well 1173 in which slit valve 162 and universalwasher 163 reside. The distal end of the middle cylinder 1160b extendsinto the relatively narrow distal end 1165 of the valve body whichcarries O-ring 161. Outermost cylinder 1160c extends from a pointproximal of said O-ring to form the relatively larger diameter portionof the valve body which carries the teeth 1169, tongue 1194, and sideport 1180. As will be seen below, the side port 1180 is actually carriedby all three cylinders.

FIGS. 11g and 11h show a slightly different embodiment of the valve body2160, valves 2162, 2163, and cannula base 2114. In this embodiment, thevalve body 2160 has a somewhat smaller overall diameter and is providedwith lateral placement or retaining wings 2160a and 2160b. Valve body2160 is also provided with a proximal annular groove 2173 for receivingthe edge of a slit valve 2162 having a substantially I-shaped crosssection. The valve body 2160 is otherwise substantially the same aspreviously described with reference to FIGS. 11a-11f, including thedistal O-ring 161, the side port 2180, the resilient tongue 2194, rampedtooth 2166, and release button 2168. The valve body cap 2164 has aninner extending annular flange 2164a for engaging washer 2163 having arippled cross section. The valve body cap 2164 is otherwisesubstantially the same as that which was previously described withreference to FIGS. 11a-11f.

The proximal mouth 2145 of the cannula base 2114 is of a somewhatsmaller diameter than the cannula base described with reference to FIGS.11a-11f, and it is provided with adjacent slots 2145a, 2145b forreceiving the wings 2160a, 2160b of the valve body 2160. In this manner,the valve assembly 2160 is located and centered in the cannula base2114, and the valve assembly 2160 cannot slide out of the side opening2180a. The external flanges 2140a, 2140b in this embodiment of thecannula base are shaped differently for easier gripping. The sidecutouts 2180a, 2144 and 2195 for receiving the side port 2180, rampedtooth 2166, and release button 2168 of the valve body are substantiallythe same as in the previously described embodiment FIGS. 11a-11f.

FIGS. 12a-12c show details of the side port 1180 of the preferredembodiment of the invention. Referring in particular to FIG. 12a, theside port 1180 is formed by a radially extending opening 1181 throughthe valve body 1160. Opening 1181 is substantially cylindrical with acentral bore 1181a communicating with the throughbore 1171 of the valvebody 1160. One end of a spring 1184 is held substantially coaxial withbore 1181a by spring stop 1181b. The other end of spring 1184 carries avalve plunger 1183 having a frustrum 1183a with vents 1183b, spring stop1183c and a plunger actuator 1183d. A female luer 1182 having a threadedluer lock 1182a and a reduced diameter extending portion 1182b and ashoulder 1182c is inserted into opening 1181 and locked and/or sealed byan adhesive, sonic welding, snap lock, or other acceptable means. Asseen in FIG. 12a, spring 1184 biases the frustrum 1183a of plunger 1183against the shoulder 1182c of luer 1182 preventing fluid passage into orout of the luer 1182. When a male luer (not shown) is coupled to thefemale luer 1182, the plunger 1183 is pressed inward against spring 1184as shown in FIG. 12b.

Referring now to FIGS. 12b and 12c, it will be appreciated that theplunger actuator 1183d is a cross (+) shaped rod having four surroundingfluid passages 1183e. Moreover, an end portion of frustrum 1183a isprovided with circumferential vents 1183b. When the plunger 1183 ispressed in away from shoulder 1182c, fluid is permitted to flow into andout of luer 1182 as a path is created from bore 1181a through spring1184, vents 1183b and passages 1183e to luer 1182.

There have been described and illustrated herein several embodiments ofa reusable trocar assembly having a disposable valve structure. Whileparticular embodiments of the invention have been described, it is notintended that the invention be limited thereto, as it is intended thatthe invention be as broad in scope as the art will allow and that thespecification be read likewise. Thus, while particular fabricationmaterials have been disclosed, it will be appreciated that othermaterials could be utilized. Also, while certain specific trocar tipshave been shown, it will be recognized that other types of trocar tipscould be used with similar results obtained. Moreover, while particularconfigurations have been disclosed in reference to the trocar handle andcannula base, it will be appreciated that other configurations could beused as well. Furthermore, while the disposable valve assembly has beendisclosed as having a slit valve or flapper valve and a universalwasher, it will be understood that different valve means housed in thevalve body can achieve the same or similar function as disclosed herein.Finally, several coupling means have been disclosed for removablycoupling the valve assembly to the cannula base. It will be understoodthat these means are exemplary and that other coupling means couldachieve substantially the same results in substantially the same manner.It will therefore be appreciated by those skilled in the art that yetother modifications could be made to the provided invention withoutdeviating from its spirit and scope as so claimed.

I claim:
 1. An automatic fluid valve permitting insertion of a surgical instrument therethrough, said automatic fluid valve comprising:a) an elastomeric member having a center and at least one slit intersecting said center, said slit permitting said surgical instrument to be inserted therethrough; and b) a plurality of raised surgical instrument engaging protrusions on a proximal surface of said elastomeric member, said protrusions being spaced away from said at least one slit.
 2. An automatic fluid valve according to claim 1, wherein:said at least one slit comprises three slits, each of said three slits extending radially outward from said center.
 3. An automatic fluid valve according to claim 2, wherein:said plurality of raised trocar engaging protrusions comprises three evenly spaced raised surgical instrument engaging protrusions.
 4. An automatic fluid valve according to claim 1, wherein:said plurality of raised surgical instrument engaging protrusions each have a coefficient of friction lower than a coefficient of friction of said elastomeric member.
 5. An automatic fluid valve according to claim 1, wherein:each of said plurality of raised surgical instrument engaging protrusions includes a portion which is substantially hemispherical in shape.
 6. An automatic fluid valve according to claim 1, wherein:each of said plurality of raised surgical instrument engaging protrusions is elongated in shape and extends radially inward towards said center along said proximal surface of said elastomeric member.
 7. An automatic fluid valve member according to claim 1, wherein:said plurality of raised surgical instrument engaging protrusions comprise a plurality of individual members insert molded in and extending through said elastomeric member.
 8. An automatic fluid valve member according to claim 7, wherein:said individual members are substantially barbell shaped.
 9. An automatic fluid valve member according to claim 1, wherein:said plurality of raised surgical instrument engaging protrusions comprise a plurality of individual members insert molded in said elastomeric member.
 10. An automatic fluid valve member according to claim 9, wherein:said individual members have a first hemispherical portion and a shaft portion coupled to said first hemispherical portion, wherein said first hemispherical portion extends outwardly from a surface of said elastomeric member, and said shaft portion is located in said elastomeric member.
 11. An automatic fluid valve member according to claim 10, wherein:said individual member further includes an anchoring portion coupled to said shaft portion, said anchoring portion extending outwardly from a second surface of said elastomeric member.
 12. An automatic fluid valve member according to claim 10, wherein:said individual member further includes an anchoring portion coupled to said shaft portion, said anchoring portion being located in said elastomeric member.
 13. An automatic fluid valve member according to claim 1, wherein:said plurality of raised surgical instrument engaging protrusions are formed from a single element insert molded in said elastomeric member.
 14. An automatic fluid valve member according to claim 13, wherein:said single element comprises one of a ring and a mesh, with said portrusions extending therefrom.
 15. An automatic fluid valve member according to claim 14, wherein:said one of a ring and a mesh comprises a ring which extends in a peripheral portion of said elastomeric member and is uninterrupted by said at least one slit.
 16. An automatic fluid valve member according to claim 1, wherein:said plurality of raised surgical instrument engaging protrusions are formed integral with said elastomeric member.
 17. An automatic fluid valve member according to claim 16, wherein:said raised surgical instrument engaging protrusions are coated with a coating having a coefficient of friction lower than a coefficient of friction of said elastomeric member.
 18. An automatic fluid valve member according to claim 17, wherein:substantially all of said proximal surface of said elastomeric member is coated with said coating having a coefficient of friction lower than a coefficient of friction of said elastomeric member.
 19. An automatic fluid valve member according to claim 1, wherein:said elastomeric member is formed of silicone, and said plurality of raised surgical instrument engaging protrusions are coated with TEFLON or an equivalent thereof.
 20. An automatic fluid valve member according to claim 16, wherein:said elastomeric member is formed of silicon, and said coating is TEFLON or an equivalent thereof. 